The impact of force equalization in minimizing the effect of drift in feedback transducers in torque-summed electromechanical actuators

Abstract

This paper focusses on implementing force equalisation to reduce or eliminate torque disparities in a four-lane torque-summed electromechanical actuator that drives the inner board aileron control surface on the Sea Harrier aircraft. Proportional, integral, and derivative control action achieved position control of the common output shaft, following two failures. The analysis included the effect of inherent motor disparities and drift in feedback transducers. Three-phase motor models were considered to account for the influence of the inherent torque ripple effect, and the influence of inertial and aerodynamic loads over various flight envelopes were also included in the analysis. Simulation tests demonstrated that although torque disparities between mismatched lanes are influenced by drift in potentiometer readings, force equalization was proven to be effective in eliminating such deviations.

Keywords

• All-electric aircraft
• Electromechanical actuators
• Force equalization
• Torque summing architecture
• Force fight